Different plastic injection molded shutters exist in the market, including customizable shutters. Customizable shutters are desirable because the costs associated with injection molds for each shutter length are high. The methods used for the customizable shutters require at least two injection molded components and a multiplicity of complex cuts to remove the excess material. In particular, the methods require the injection molding of a standard shutter and the injection molding of the shutter ends, which are removed from the original shutter when the excess material is removed. The removal of the excess material involves a series of cuts, including angled and straight lines, along the seams formed in the shutter designs. These assemblies can be higher in cost due to the multiple injection molded components, the complex cutting pattern, and the extra material waste. And because the assembly processes include multiple injection molded components, the components can be slightly dissimilar in coloration. It would be desirable to provide a method of customizing a shutter having a single injection molded component and less material waste. Therefore it is an objective of the present invention to provide a method of reducing the length of a standard shutter using a single injection molded shutter.